Drug Dependence

Question 1

Psychoactive Drugs

Answer 1

drugs that can alter our consciousness and perceptions

-4 main categories: depressants, stimulants, hallucinogens, and opiates

Question 2

Depressants

Answer 2

• lower body’s basic functions - decrease heart rate, decrease blood pressure
• lower neural activity - lower CNS activity (decrease arousal/stimulation in areas of our brain); decreased processing and reaction time
• act on GABA-gated Cl- channels by opening them and essentially hyperpolarizing cell (inhibiting excitation)

Question 3

Alcohol

Answer 3

• decreased inhibitions so decreased cognitive control; reduced self awareness and self control
• lack of coordination, slurring of speech
• think more slowly, disruption of REM sleep (and formation of memories)
• CNS depressant absorbed through cell membrane

Question 4

Barbituates

Answer 4

• used to induce sleep or reduce anxiety (calm them down)
• CNS depressant; anesthetic or anticonvulsant
• Negative Side Effects: reduced memory, judgment and concentration, and dangerous when taken with alcohol

Question 5

Benzodiazepines

Answer 5

• most commonly prescribed
• sleep aids, anti-anxiety, anticonvulsant
• enhance brain’s response to GABA; open up GABA-activated chloride channels in neurons leading to hyperpolarization
• short acting and intermediate acting = sleep; long acting = anxiety

Question 6

Stimulants

Answer 6

drugs excite your CNS, increase HR/BP, alertness, more awake, more energetic
-stimulants and depressants are functionally opposite but do not work on the same things at a physiological level

Question 7

Caffeine

Answer 7

inhibition of adenosine receptors by breakdown of cAMP; disrupt sleep and increase energy

• physiologically addicting
• Withdrawal Symptoms: irritability, difficulty concentrating, depression

Question 8

Nicotine

Answer 8

increase HR/BP; disrupts sleep and suppresses appetite (leading to metabolic problems causing weight gain)

• at high levels, nicotine can cause muscles to relax and release stress-reducing neurotransmitters (to counteract hyper-alertness)
• nicotine works as acetylcholine receptor agonist
• physiologically addicting
• Withdrawal Symptoms: anxiety, insomnia, irritability, distractibility

Question 9

Amphetamines and Methamphetamines

Answer 9

trigger release of dopamine; feeling of euphoria for up to 8 hours

• Aftermath: irritability, seizures, depression, insomnia
• meth is highly addictive and long-term meth addicts may lose ability to maintain normal level of dopamine because brain tries to adjust to intense highs
• block the reuptake of dopamine stimulating an increase in the release of dopamine from presynaptic membrane